As the author points out, the sum of obstetric knowledge has not been greatly advanced, since the publication of the second edition, but there have been several valuable additions. More important, however, time has been allowed for ascertaining the true valuation of several obstetric problems and methods that had not been thoroughly tried out up to that time. He mentions specifically the pregnancy reaction of Abderhalden, the relation of the endocrine glands to gestation, twilight sleep, and the urinary tests for the toxemias of gestation. Amplifications have been made in such obstetric problems and methods as anesthesia, analgesia, cesarean section and the treatment of contracted pelvis. In the treatment of eclampsia, more prominence is given to conservative methods, and as a result of the advance in the use of the rectal method of examination during labor, the section on the conduct of labor has been revised with this point in